Electrostatic clamps or chucks (ESCs) are often utilized in the semiconductor industry for clamping workpieces or substrates during plasma-based or vacuum-based semiconductor processes such as ion implantation, etching, chemical vapor deposition (CVD), etc. Conventionally, a semiconductor processing system and associated ESC is designed to clamp a workpiece by energizing electrodes associated with the ESC by one of alternating current (AC) or direct current (DC). Often, temperatures at which the workpiece is processed dictates whether AC or DC power is utilized. For example, under low processing temperature conditions, DC power can be utilized to attain greater clamping forces than AC power. However, DC power has drawbacks, such as inducing residual clamping forces after the DC power is removed.
At higher temperatures, AC power can be utilized, as resistivity of the ESC decreases as processing temperatures increase, and lower voltage AC power can be advantageous. Further, de-clamping times can be decreased by utilizing AC power at such higher temperatures. As such, sufficient clamping forces can be attained by utilizing AC power at higher temperatures.
Conventionally, however, ESCs have a predetermined style or pattern of electrodes that is optimized for AC or DC operation of the ESC. Accordingly, a first ESC and power supply is typically used for AC operation, while a second ESC and power supply are utilized for DC operation, where each of the first and second ESCs have corresponding electrode patterns optimized for their respective AC or DC operation. Accompanying costs and system downtime are typical when changing ESCs, thus deleteriously affecting production.